Undeterred by the reversal of transport fare hikes that sparked the protests, and promises of better public services, demonstrators marched around two international soccer matches and in locales as diverse as the Amazon capital of Manaus and the prosperous southern city of Florianopolis.

While the protests remained mostly peaceful, the growing number of participants led to occasional outbursts of violence and vandalism in some cities. In central Rio de Janeiro, where 300,000 people marched, police afterwards chased looters and dispersed people crowding into surrounding areas.

"Twenty cents was just the start," read signs held by many converging along the Avenida Paulista, the broad avenue in central São Paulo, referring to the bus fare reductions. Police there said 110,000 people lined the avenue.

In the capital, Brasilia, tens of thousands of protesters marched around the landmark modernist buildings that house Congress and the Supreme Court and briefly set fire to the outside of the Foreign Ministry. Police said about 80 of the protesters, some with homemade explosives, made it into the ministry building before they were repelled.

In Ribeirão Preto, near São Paulo, a 20-year-old demonstrator died after a driver plowed a jeep into a crowd. Brazilian media reported hundreds of minor injuries across the country, including a Rio television reporter who recounted being hit by a rubber bullet fired by police.

The swelling tide of protests prompted President Dilma Rousseff to cancel a trip next week to Japan, her office said. The president, whose administration was caught off-guard by the rapid growth of the demonstrations, also planned an emergency meeting for Friday, a government source said.

The targets of the protests, now in their second week, have broadened to include high taxes, inflation, corruption and poor public services ranging from hospitals and schools to roads and police forces.

With an international soccer tournament as a backdrop, demonstrators are also denouncing the more than $26 billion of public money that will be spent on the 2014 World Cup and 2016 Olympics, two events meant to showcase a modern, developed Brazil.

"This is fair play," read a banner among the hordes in Brasilia, a twist on the slogan used to promote sportsmanship by FIFA, world soccer's governing body.

MULTIPLE GRIEVANCES

After the concession on transport fares on Wednesday, activist groups differed over what their next priority should be. On Facebook, Twitter and other social media, some Brazilians expressed disgust for the scattered violence and vandalism that marred some of the marches.

The competing demands of demonstrators appeared to add to the intensity of Thursday's protests.

"What am I protesting for?" asked Savina Santos, a 29-year-old civil servant in Sao Paulo. "You should ask what I'm not protesting for! We need political reform, tax reform, an end to corruption, better schools, better transportation. We are not in a position to be hosting the World Cup."

Inside Rio's iconic Maracanã stadium, soccer fans sang protest songs and showed support for the throngs of demonstrators gathering in the city. In Salvador, a northeastern city hosting another game of the soccer tournament that serves as a World Cup test run, protesters pelted a FIFA bus with rocks.

Police in Salvador, Rio, Brasilia and other cities used tear gas, pepper spray and other tools to disperse crowds. They donned riot gear and used horses, trucks and barricades to help channel the crowds and protect buildings.

The unrest comes six months before an election year and just as Brazil, after nearly a decade-long economic boom in which the country's profile soared on the global stage, enters a period of uncertainty. Economic growth of less than 1 percent last year, annual inflation of 6.5 percent and a loss of appetite for Brazilian assets among international investors have clouded what had been a feel-good era for Brazil, a country of nearly 200 million people.

Brazil's currency, the real, dropped to a four-year low on Thursday, trading as weak as 2.275 per U.S. dollar. The country's benchmark stock market index, the Bovespa, also hit a four-year low.

CHANGING POLITICAL LANDSCAPE

The protests have shaken the once solid ground under Rousseff and her ruling Workers' Party, a bloc that grew out of convulsive demonstrations by Brazil's labor movement 30 years ago. Until inflation and other economic woes began eroding her poll numbers in recent weeks, Rousseff enjoyed some of the highest approval ratings of any elected leader worldwide.

The demonstrations have been comprised of mostly middle-class, well-educated voters who do not form the bulk of Rousseff's electoral base. The president and her party have sought to get ahead of the complaints and embrace them as their own - a shift that contrasts sharply with a playbook that long relied on telling Brazilians that they had never had it so good.

With little more than a year to go before presidential and gubernatorial elections, the unrest is forcing incumbents and traditional political parties to reconsider their strategies.